drm/meson: Correct OSD1 global alpha value

[ Upstream commit 955d8719516428357dbda7e1f1d146cf6ca6ae41 ]

VIU_OSD1_CTRL_STAT.GLOBAL_ALPHA is a 9 bit field, so the maximum
value is 0x100 not 0xff.

This matches the vendor kernel.

Signed-off-by: Stuart Menefy <stuart.menefy@mathembedded.com>
Fixes: e5a2f708e761 ("drm: Add support for Amlogic Meson Graphic Controller")
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220908155103.686904-1-stuart.menefy@mathembedded.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/meson/meson_plane.c b/drivers/gpu/drm/meson/meson_plane.c
index ed543227b00dd9c60f39c46a0b9369fe57f093df..53f5d0581c3550c71aac626f05ff5e84262abf4a 100644 (file)
--- a/drivers/gpu/drm/meson/meson_plane.c
+++ b/drivers/gpu/drm/meson/meson_plane.c
@@ -128,7 +128,7 @@ static void meson_plane_atomic_update(struct drm_plane *plane,
 
        /* Enable OSD and BLK0, set max global alpha */
        priv->viu.osd1_ctrl_stat = OSD_ENABLE |
-                                  (0xFF << OSD_GLOBAL_ALPHA_SHIFT) |
+                                  (0x100 << OSD_GLOBAL_ALPHA_SHIFT) |
                                   OSD_BLK0_ENABLE;
 
        canvas_id_osd1 = priv->canvas_id_osd1;